Vehicle seats have traditionally been costly to make because they require so many components such that they tend to be fairly labor intensive. As a result, vehicle seats tend to be costly to make and service.
Vehicle seats typically have a base that provides a framework or support for the rest of the seat. The seat base, also commonly referred to as a seat pan, is structurally more rigid than each seat cushion mounted to it. As a result, the base is what gets connected to the vehicle frame or chassis, whether it be by direct attachment or via a seat slide mechanism designed to permit the seat to be moved forwardly or backwardly.
While made of metal in the past, the present day seat base is almost always formed of plastic because it is cheaper and, in many instances, more versatile. Despite these advantages, it has not changed the fact that vehicle seat assembly still remains a costly assembly intensive process requiring many separate components to complete.
One area where this still is true relates to the components and assembly process required to attach the seat base, and hence the seat, to a vehicle. Mounting brackets used to secure each base of a particular vehicle seat to the vehicle commonly are secondary components that are typically attached to the base before vehicle assembly. Most commonly, the mounting brackets are attached to the seat base when it or some other part of the vehicle seat is being manufactured such that the seat often arrives for vehicle assembly with the mounting brackets pre-assembled.
Presently, either threaded inserts are used to attach the bracket to the base or the bracket itself is incorporated into the base, typically by molding them in place in the base when the base is formed. The use of threaded inserts molded into the base means that the mounting bracket must be attached to the base using threaded fasteners that are threaded into each insert, which undesirably increases part count, assembly steps, and, of course, cost. Molding the bracket in place into the base, which is a common injection molding practice, decreases part cost but often can significantly increase the cost of the injection molding tooling. In addition, the process cycle time to mold a base where the bracket is molded-in-place is slower, which can undesirably significantly increase the total cost to mold the base as a result. Finally, molding the bracket in place limits flexibility because once the bracket is molded, it cannot be removed and changed independent of also changing the entire seat base.
Another area where this is particularly true relates to seat cover attachment to the seat base. Conventional methods for securing the cover to the base typically require separate components, usually fasteners or the like, to attach the cover to the base. Often special tools, equipment, and/or fixtures are also required. For example, staples, clips, cords, wires and hog rings, rivets, adhesives or the like are commonly used to attach a seat cover to a seat base.
While the use of any of these methods is labor intensive and costly, there are other factors that further increase costs. For example, since all of these methods tend to permanently fix the cover to the base, anything that occurs during assembly that results in less than an aesthetically pleasing looking cover often requires the cover be pulled off and scrapped or reattached. This happens far too frequently because seat cover attachment is so dependent on the skill of the assembler that it has been difficult, if not impossible, heretofore to ensure repeatability of seat cover attachment.
Therefore, there is a need to provide a seat assembly system that overcomes one or more of these deficiencies. There also is a need to provide a seat bracket and base arrangement that overcomes at least one of the aforementioned bracket assembly deficiencies. And there is a need for an improved seat cover attachment arrangement and method.